Elevator control system



Dec. 5, 1933.

R. NEUSCHOTZ I ELEVATOR CONTROL SYSTEM 7 Filed Feb. 2, 1951 I N V EN TOR.

BY 5 ATTORNEY Patented Dec. 5, 1933 onrrosTArEs PATENT OFFICE 1,938,109 ELEVATOR CONTROL SYSTEM Robert Neuschotz, New York, N. Y. Application Eebrnaryz, 1931. Serial No. 512,788

19 Claims. (01. 187-31) This invention relates to elevator control systems and is particularly directed. to the type of system wherein the hoisting motor is controlled by movement of the elevator doors. In usual practice, switches or contacts are provided for the elevator shaft doors and for the car door, and said switchesare arranged to close upon closing of the doors, and are so operated and interconnected that unless the shaft door or doors and the car door are in fully closed position or within a. predetermined distance of full closure, the hoisting motor will be maintained inoperative.

Ordinarily the door switches are set to close between the full closure position of the doors and a predetermined distance, for example, four inches from the point at which the doors are actually closed. The door switches'and the car switch are usually interconnected in series circuit so that upon closingof the last door and hence its switch, closing of the'car switch by the car operator will cause'initiation of flow of current to the controller for operating the hoisting motor. A fraction of a second later, for example, six-tenths of a second, the usual controller relays and contactors having been operated and the inertia of the'hoisting mechanism having been overcome, the elevator begins to move.

It is an object of this invention to eliminate as much as possible of this fraction of a second consumed from the closing of the last elevator door switch and the inception of movement of' the elevator car. To this end'my system has essentially several circuits, one similar to the ordinary door switch or contact system now in 4 use and another circuit interconnected therewith. The door switches of the first circuit may be set to close several inches back of the usual four'inch zone so that initiation of the flow of current for operating the hoisting motor is advanced in time. with respect to closure of the door, for example, when the door is. about twelve inches from the actual closed position. Said other circuit likewise includes door switches which may beset to close at a point'between full closure position and the usual four inches from-said full closure position (i. e., within'the fourinch zone, for example).

In accordance with my invention the circuits are so interconnected that'if the door has been closed sufiiciently to close the door switch-of the circuit and has not reached the second switc before the car actually starts to move, or before a time switch interposed in t e first circuit closes, the current will be automatically cut off from the hoisting motor which will then remain inoperative until the door closes the second door switch, at which time the flow of current is once more initiated.

A further object of this invention is to provide a simple control system of the character de- 60 scribed which shall be comparativelyinexpensive to manufacture and install and which shall yet be positive and smooth in operation and practical and efiicient to a high degree in use.

Other objects of this invention will in part-be 65 obvious and in part hereinafter pointed out.-

The invention accordingly consists in the features of construction, combinations of elements and arrangement of parts which will be exemplified in the construction hereinafter described 7 and of which the scope of application will be indicated in the following claims.

In the' accompanying drawing, in which is shown one of the various possible embodiments of this invention, f

The figure is a diagrammatic view of the elevator control system embodying my invention.

Referring now in detail to the drawing, 10 designates a control system for elevators wherein the hoisting motor is controlled by movement of the doors of the elevator shaft and the elevator car.

In usual practice, each of the elevator shaft doors and the elevator door'or the door operating mechanism are adapted to close a door contact switch at a predetermined position of said door from the full closure position thereof, and all of the switches are interconnected in series circuit with the hoisting motor circuit and with the car operating switch, so that when all the 0' door contact switches are closed, movement. of the car operating switch, by the car operator to closed position will complete a circuit for operating the hoisting motor, and the car will begin to move a fraction of a second later, some time being consumed by the inertia of the parts and/or for operating controller relays and contactors.

In usual practice, the door contacts are so arranged as to close a few inches from the full 1 closure positions of the doors, for example, four inches. 'For eliminating as much as possible the time consumed between the full closure of said doors and the beginning of movement of the elevator car, whereby the travel time between floors is reduced, I have provided a plurality of circuits interconnected and arranged with respect to the elevator doors, the car and the motor in the manner hereinafter described in detail.

Designated on the drawing by numeral 11, is the hoisting motor connected to one side of a suitable electric power source, for example, the minus terminal by a conductor 12. The other side or plus terminal of the power source is connected by means of a conductor 13 to the usual controller or reversing mechanism 14. well-known in the art. The controller mechanism is connected by conductor 15 to one terminal 15 of the remote manual control for the hoisting motor, here shown in the form of the car switch, located within the elevator car. The other terminal 17 of the remote control is connected by conductor 18 to the controller mechanism 14 for reversing the direction of the motor, in the well-known manner.

A remote control switch arm 19 is pivoted as at 20 and connected by conductor 21 to a movable door contact switch 22 forming part of a primary circuit A. The switch 22 is adapted to be closed by a door or movable member 23, which may either be one of the elevator shaft doors or the elevator car door.

Each of the doors 23 is provided with a switch 22, said switches being preferably similarly spaced with respect to the closing position of the doors and interconnected by means of conductors 24 in series circuit.

In the drawing, for the purpose of illustration only, two switches 22 are shown connected in series circuit, it being understood however, that any number of such switches may be provided, depending upon the number of doors and if there are more than one of said switches in the circuit A, they areinterconnected in series circuit so that the circuit A will not be closed until the last door switch has been moved to closing position.

In the drawing, the lower switch 22 is shown in closed position, the roller 25 at the end of the' switch arm 22 having been moved upwardly by the cam or ramp 26 on the door. The upper switch 22 however, is shown in open position and the upper door 23 is shown in dotted lines, partially and in opened position. For the purpose of illustration only, it will be assumed that the two switches 22 shown, are end switches of the entire series of car and shaft door switches.

Means is provided to automatically open or break the circuit A at a predeter .ined time after the initiation of flow of current in said circuit for operating the hoisting motor, and preferably before actual .mcvernent or" the elevator car begins so that the hoisting motor becomes inoperative before the car starts to move. To this end, the upper switch 22 therefore shown as connected by means of conductor 2''! to the fixed terminal 28 or a normally closed switch 29, said switch forming part of a relay 53 and comprising a movable arm 30 connected conductor 31 to a coil 32. For the purpose hereinafter appearing, the coil 32 is adapted to energize a time element or retarded switch 33, that is, upon energizing the coil 32, the switch 33 will close slowly for the purpose hereinafter described, due to a dash pot mechanism 35 or similar retarding device. The switch 33 be operated by a motor interposed in said circuit A or may be dependent upon the magnitude of the starting current to the hoisting motor. The coil 32 is connected by conductor 36 to the controller mechanism 14 which in turn is connected by conductor 38 to the hoisting motor.

It will now be seen that when all the doors are closed and the arm moved to the left into contact with the terminal 16, t is flow of current in the circuit A will be initiated for operating the controller and hence the hoisting motor. The elevator however, does not begin to move until a fraction of a second or some time later, for example of a second. The time consumed between the completing of the circuit of the motor and the starting of the elevator is due usually to inertia of the parts, operation of the controller relays and contactors and for other reasons. In usual practice, the switches 22 are so placed with respect to the doors as to be closed a few inches from the point of actual closure of the doors, for example, not more than four inches as required by the New York building code.

In accordance with my invention, however, the switches 22 are so placed as to be closed a few inches before the usual four inch zone. For example, the switches 22 may be placed so as to be closed 12 inches from the points of full or actual closure of the doors, so that the closing of the circuit A is advanced in time.

For opening the switch 29 automatically as soon as the time switch 33 closes, the coil 53 of relay 52 is interposed in and forms part of a circuit C, one side or" said coil being connected by conductor 54 to one terminal of the power source, for example, the minus terminal. The other side of the coil 53 is connected through conductor 55 to a fixed terminal 56. A second fixed terminal 56a is provided spaced from terminal 56, said terminals being adapted to be bridged by the retarded switch 33. Said terminal 56ais connected by conductor 5'7 to a terminal 58 of a normally closed switch 59, forming part of relay 49, said switch being connected by conductor 60 to the other side or plus terminal of the power source.

The time relay 33 is preferably so constructed as to close in somewhat less time than is consumed between the closing of the circuit A for the hoisting motor and the beginning of movement of the elevator car. For example, if it requires of a second for starting travel of the elevator, the time relay switch 33 may be set to close in 0i 2. second, so that said switch ordinarily will close before the elevator starts to move. Should the lever 19 be moved to the left, for example, into contact with the terminal 16, and the elevator door moved toward closing position, the doors on the shaft being closed, the circuit A will be completed when the elevator door is about twelve inches from the full closing position and current caused to flow to the hoisting motor.

Thus, should the door 23 be moved only far enough to close the switch 22 for completing the circuit A, the switch 59 eing normally closed, the relay 53 will be actuated as soon as switch 33 closes, for automatically opening the switch 29, and breaking the circuit before the elevator starts to move.

Means is provided however, to prevent opening of the switch 29 upon closure of the time switch. To this end, I provide a third circuit B comprising door contact switches 40 so placed as to close within the usual four inch zone or at closer points to full closure position than the switches 22. Each of the switches 40 is likewise provided with rollers or followers 41 adapted to be contacted by the cam or ramp 26 on the door 23. The switches 40 may be interconnected in series circuit by means of conductors 42. The uppermost or last switch 40 on one side of the series of switches may be connected by means of conductor 43 to the conductor 38 and hence to "I second switch, prior to the closing of said first switch, and means for cutting off the flow of current from said motor upon failure of said door to close said first named switch within a predetermined time after closing said second switch.

4. In combination with an elevator hoisting motor, an electric circuit for supplying electric power to said motor, a switch controlled by movement of an elevator door, interposed in said circuit and adapted to be closed for initiating flow of current to said motor, a second door controlled switch, and means for automatically opening said circuit, upon failure to close said second switch within a predetermined time after closure of said first switch.

5. In combination with an elevator shaft, an elevator car therein and a motor for hoisting said car, means for supplying electrical energy to said motor, including acircuit, a switch controlled by movement of an elevator door, interposed in said circuit and adapted to be closed for initiating flow of current to said motor, and means controlled by said door for automatically preventing movement of the elevator car after said circuit has been closed, said means comprising means for opening said circuit before the elevator car begins to move.

6. In combination with an elevator car having a door and a hoisting motor for said car, an electric circuit for supplying power to said motor, a door switch adapted to be closed by said door interposed in said circLL t, a remote control car switch interposed in said circuit and connected in series with said door switch, said circuit being adapted to be closed upon closure of said switches, a third switch interposed in said circuit, means for opening said last switch a predetermined time after closure of said first two switches, and means controlled by movementof said door for preventing opening of said last named switch.

7. In combination with a motor, an electric circuit for supplying power to said motor including a remote control switch interposed in said circuit, a manually movable member, a switch adapted to be closed at a predetermined point in the movement of said member, interposed in said circuit and connected in series with said first mentioned switch, a third switch interposed with in said circuit, electric means for opening said switch, and means for preventing opening of said switch, said last means comprising a second electric circuit, and a switch interposed in said last named circuit and adapted to be closed at another predetermined point in the movement of said movable member for closing said last named circuit.

8. In combination with an elevator car having a door and a hoisting motor therefor, means for supplying electric current to said motor, said means including a door contact switch adapted to be closed by said door at a predetermined distance from the full closure position thereof, means for thereafter cutting off supply of current to said motor, and means to prevent actuating of said last mentioned means, including a second switch controlling said current supplying means, adapted to be closed by said elevator door at a second lesser predetermined distance from the full closure position thereof.

9. In combination with an elevator car having a door, adapted to move in an elevator shaft, a hoisting motor for said elevator car, means for supplying electric current to said motor includ ing an electric circuit, door contacts for the elevator doors, in said circuit, each adapted'to close at a' predetermined distance from the full closure position of said doors, said contacts being connected in series circuit to each other, another switch interposed in said circuit, and means for automatically opening said last switch upon failure ofone of said doors to reach another shorter predetermined distance from the full closure position thereof.

10. In combination with an elevator car having a door, adapted to move inan elevator shaft, a hoisting motor for said elevator car, means for supplying electric current to said motor, including an electric circuit, door contacts for the ele=- vator doors, in said circuit, each adapted to close at a predetermined distance from the full closure position of said doors, said contacts being con nected in series circuit to each other, another switch interposed in said circuit, and means for automatically opening said switch upon failure of one of said doors to reach another lesser pre'-- determined distance from the full closure'posi tion thereof, within a predetermined time after said circuit has been closed.

11. In combination with an elevator car having a door, adapted to move in an elevator shaft, :3. hoisting motor for said elevator car, means for supplying electric current to said motor, including an electric circuit, door contacts for the doors, in said circuit, each adapted to close at a predetermined distance from the full closure position of said doors, said contacts being connected in series circuit to each other, another switch interposed in said circuit and means for automatically openingsaid switch upon failure of one of said doors to reach a lesser predetermined distance from the full closure position thereof, within a predetermined time after said circuit has been closed, said means including a relay adapted to open said last named switch, an electric circuit for said relay, said circuit having 'a pair of spaced contacts, and a time switch interposed within said first circuit adapted to bridge said contact a predetermined time after the closing of said first circuit.

12. In combination with an elevator car having a door, adapted to move in an elevator shaft, a hoisting motor for said elevator car, means for supplying electric current to said motor including an electric circuit, door contacts for the elevator doors, in said circuit, each adapted to close at a predetermined distance from the full closure position of said doors, said contacts being connected in series circuit toeach other, another switch interposed in said circuit, and means for automatically opening said switch upon failure of one of said doors to reach a lesser predetermined distance from the full closure position thereof, within a predetermined time after said circuit has been closed, said means including a relay adapted to open said last named switch, an electric circuit for said relay, said circuit having a pair of spaced contacts, a time switch interposed within said first circuit adapted to bridge said contacts at a predetermined time after the closing of said first circuit, and another switch interposed within said second circuit, said switch being normally closed, means for opening said switch to prevent energizing of said relay upon closure of said time switch, a second relay for opening said normally closed switch, and means for energizing said last named relay. I

13. In combination with an elevator car having a door, adapted to move in an elevator shaft, a

one side (plus side) of the hoisting motor 11. The

lowermost or last switch 40, on the other side of the "series of switches, may be connected by means of conductor 4'7 to the coil 48 of a relay 49.

- Said coil may be connected by conductor 50 to the other side of the hoisting motor of the minus terminal.

, Thus, should the door, after closing switch 22, continue to be moved to closing position, and the switch 40 closed before the switch 33. closes, then the switch 59 will have been opened by relay 49, and the circuit for the relay 52 broken to the door, whereby the travel time of the car, that is, the time consumed between the full closing of the elevator door and the reaching of the next adjacent floor, is effectively reduced. In other words, instead of the car beginning to moveabout of a second after the door reaches the door contact within the four inch zone, the car starts substantially 1 a of a second after the door closes the door switch 40 within the four inch zone. Means is also provided to prevent movement of, the elevatorvcar before the door has reached the second door switch 40 and is within the usual four inch zone, as described above.

It will now be understood that the relay 49 must be energized before the time element switch 33 closes, or within the predetermined time after initiating flow of current to the motor, to prevent'the motor circuit from being rendered inoperative. Thus, should the door be closed only sufficiently to complete the circuit A. and then stopped so as to prevent completion of the circuit B, the motor circuit will merely be automatically rendered inoperative as soon as the time element switch closes.

It willnow be further understood that the relay 49 is connected across the motor circuit; that is-the relay circuit can only be energized when the motor circuit is energized and hence when the motor is dead no current will flow through said relay. At night, for example, therefore, when all of the elevator doors are closed, there will be no current flowing through the relay 48 and hence no drain of power. It is only when the switch 19 is moved to either the right or the left to close the motor circuit, that the circuit through the relay 48 may be energized. This is so since the coil 48 is connected through conductor 50 to one side of minus terminal, of the power source, and throughconductors 4'7, switches 40 and conductor 43 to the conductor 38, then through the controller mechanism to conductor 36, then through switch 29 tothe conductor '27 and then through the conductors 24 and 21 to the arm 19 which in turnis connected to the other side or the plus terminal of the power source. 7

For starting the car, while the doors are open, for example, in cases of emergency, I provide a pair of conductors 60 and 61 connected to the conductors 43, 47 respectively, and a second pair of conductors 62 and 637connected to the conductors 2'7 and 21 respectively. A switch 65 may be provided for closing the circuit for the conduc'ors 60 61 and the conductors 62 and 63, either simultaneously or selectively. Upon closing the switch 65, the contact switches for the circuits A and B are shunted and the motor circuit closed and the circuit for the relay 49 likewise closed for opening the switch 59 to per-- mit the elevator to start upon closing of the time switch 33.

In the claims, the term elevator door will be understood to designate either an elevator car door or an elevator shaft door. Although switches 22 and 40 are described as being operated by the doors 23, it will be understood that the" said switches may be closed by means of mechanism used to close the doors, or the contact switches on the car may be operated by all the doors in the shaft by any suitable means, for example, an extending cam on said shaft doors engaging said elevator car switches when the car is in proper position at the various floors for such engagement. Although the circuit A is shown as connected to the controller, it is obvious that said circuit may be directly connected to a hoisting motor. In any event, initiation of flow of current in the circuit A will cause operation of and hence initiation of a flow of current in the hoisting mo'or through the controller relays. Thus the term for initiating flow of current to the,

hoisting motor in the specification or claims, means either directly or through the controller relays.

It will thus be seen that there is provided a device in which the several objects of this invention are achieved, and which is well adapted to meet the conditions of practical use.

As various possible embodiments might be made of the above invention, and as various changes might be made in the embodimentabove set forth, it is to be understood that all matter herein set forth or shown in the accompanying drawing is to be interpreted as illustrative and not in a limiting sense.

Having thus described my invention, I claim as new and desire to secure by Letters Patent:

1. In combination with an elevator motor an elevator car, a part movably mounted on oar, means controlled by said movably mounted part in one position thereof for initiating flow of current to said motor, time controlled means, controlled by said first means, for thereafter cutting off the current to said motor to prevent the latter from beginning to operate, and means controlled by said movably mounted part in another position thereof for rendering said time controlled means inoperative, to permit operation ofsaid motor.

2. In combination with an elevator car and an elevator door, a hoisting motor for said car, a

switch controlling the operation of said motor,

means for auiomatically closing said switch dur ing movement of said door toward closing position, means for initiating fiow of current to said motor prior to the closing of said switch, said means including a second switch, and means for closing said second switch during closing movement of said door prior to the closing of said first switch, and means for cutting off the flow of current from said motor upon failure of said door to close said first switch, after closing said second named switch.

In combination with an elevator car having a door, a hoisting moorfor said car, a door contact switch controlling the operation of said motor, means operatively associated with said i.

cluding a second door contact switch, means operatively associated with said door for closing said hoisting motor for said elevator car, means for supplying electric current to said motor including an electric circuit, door contacts for the elevator doors, in said circuit, each adapted to close at a predetermined distance from the full closure position of said doors, said contacts being connected in series circuit to each other, another switch interposed in said circuit and means for automatically opening said switch upon failure of one of said doors to reach a lesser predetermined distance from the full closure position thereof, within a predetermined time after said circuit has been closed, said means including a relay adapted to open said last named switch, an electric circuit for said relay, said circuit having a pair of spaced contacts, a time switch interposed in said first circuit adapted to bridge said contacts at a predetermined time after the closing of said first circuit, and another switch interposed in said second circuit, said switch being normally closed, means for opening said switch to prevent energizing of said relay upon closure of said time switch and a second relay for opening said normally closed switch and means for energizing said second relay, said means comprising a plurality of switches connected with said elevator shaft doors and adapted to be closed at said lesser predetermined distance from the full closure position of said doors.

14. In combination with an elevator car having a door and a hoisting motor therefor, means for supplying electric current to said motor, said means including a door contact switch adapted to be closed by said door at a predetermined distance from the full closure position thereof, means for thereafter automatically cutting off supply of current to said motor, means to prevent actuation of said last mentioned means, including a second switch adapted to be closed by said elevator door at a second predetermined distance from the full closure position thereof, and manually actuated electrical means for cutting out said switches whereby said elevator car may be moved with said door open.

15. In combination with an electric elevator hoisting motor, an electric circuit for supplying power to said motor, a switch controlled by movement of an elevator door interposed in said circuit and adapted to be closed for initiating flow of current to said motor, and a time controlled switch controlled by said circuit, arranged for automatically opening said circuit a predetermined time after said circuit is closed.

16. In combination, an elevator car having a door, a hoisting motor for said car, means for supplying electrical energy for operating said motor including a circuit, a switch within said circuit controlled by the elevator car door in one position thereof for closing said circuit to initiate flow of current to said motor, means for opening said circuit after said circuit has been closed to prevent the motor from beginning to operate, and means controlled by said door in another pcthereof for preventing opening of said circuit to permit operation of said motor.

17, In combination, an elevator car having a door, a hoisting motor for said car, means for supplying electrical energy to said motor including a circuit, a switch within said circuit adapted to be closed by the elevator car door for closing said circuit to initiate flow of current to said motor, means for opening said circuit after said circuit has been closed to prevent the motor from beginning to operate, and means controlled by said door for preventing opening of said circuit to permit operation of said motor, said last named door controlled means comprising a second switch adapted to be closed by said door after said first switch has been closed by said door.

18. In combination with a member movable in a shaft and a hoisting motor for said member, means for operating said motor including a circuit, a second movable member, means controlled by said member in one position thereof for closing said circuit to permit operation of said motor, time controlled means for opening said circuit to prevent operation of said motor, and means con trolled by said second movable member in another position thereof, for preventing said time controlled means from opening said circuit.

19. In combination with a member movable in a shaft, a motor for hoisting said member, means for operating said motor including a circuit, a second movable member, means controlled by said second member for closing said circuit to permit operation of said motor after inertia has been overcome, time controlled means, controlled by said first means, for opening said circuit before inertia has been overcome to prevent the motor from starting to operate, and means controlled by said second movable member for preventing said circuit from being opened by said time controlled means, whereby said motor will operate after inertia has been overcome.

ROBERT NEUSCHOTZ. 

